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    <title>Vector Label Decluttering</title>
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          <h4 id="title">Vector Label Decluttering</h4>
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          <p id="shortdesc">Label decluttering with a custom renderer.</p>
          <div id="docs"><p>Decluttering is used to avoid overlapping labels with <code>overflow: true</code> set on the text style. For MultiPolygon geometries, only the widest polygon is selected in a custom <code>geometry</code> function.</p>
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          <div id="api-links">Related API documentation: <ul class="inline"><li><a href="../apidoc/ol.Map.html" title="API documentation for ol.Map">ol.Map</a></li>,<li><a href="../apidoc/ol.View.html" title="API documentation for ol.View">ol.View</a></li>,<li><a href="../apidoc/ol.extent.html" title="API documentation for ol.extent">ol.extent</a></li>,<li><a href="../apidoc/ol.format.GeoJSON.html" title="API documentation for ol.format.GeoJSON">ol.format.GeoJSON</a></li>,<li><a href="../apidoc/ol.layer.Vector.html" title="API documentation for ol.layer.Vector">ol.layer.Vector</a></li>,<li><a href="../apidoc/ol.source.Vector.html" title="API documentation for ol.source.Vector">ol.source.Vector</a></li>,<li><a href="../apidoc/ol.style.Fill.html" title="API documentation for ol.style.Fill">ol.style.Fill</a></li>,<li><a href="../apidoc/ol.style.Stroke.html" title="API documentation for ol.style.Stroke">ol.style.Stroke</a></li>,<li><a href="../apidoc/ol.style.Style.html" title="API documentation for ol.style.Style">ol.style.Style</a></li>,<li><a href="../apidoc/ol.style.Text.html" title="API documentation for ol.style.Text">ol.style.Text</a></li></ul></div>
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          <textarea class="hidden" name="title">Vector Label Decluttering</textarea>
          <textarea class="hidden" name="description">Label decluttering with a custom renderer.</textarea>
          <textarea class="hidden" name="js">var map &#x3D; new ol.Map({
  target: &#x27;map&#x27;,
  view: new ol.View({
    center: [0, 0],
    zoom: 1
  })
});

var labelStyle &#x3D; new ol.style.Style({
  geometry: function(feature) {
    var geometry &#x3D; feature.getGeometry();
    if (geometry.getType() &#x3D;&#x3D; &#x27;MultiPolygon&#x27;) {
      // Only render label for the widest polygon of a multipolygon
      var polygons &#x3D; geometry.getPolygons();
      var widest &#x3D; 0;
      for (var i &#x3D; 0, ii &#x3D; polygons.length; i &lt; ii; ++i) {
        var polygon &#x3D; polygons[i];
        var width &#x3D; ol.extent.getWidth(polygon.getExtent());
        if (width &gt; widest) {
          widest &#x3D; width;
          geometry &#x3D; polygon;
        }
      }
    }
    return geometry;
  },
  text: new ol.style.Text({
    font: &#x27;12px Calibri,sans-serif&#x27;,
    overflow: true,
    fill: new ol.style.Fill({
      color: &#x27;#000&#x27;
    }),
    stroke: new ol.style.Stroke({
      color: &#x27;#fff&#x27;,
      width: 3
    })
  })
});
var countryStyle &#x3D; new ol.style.Style({
  fill: new ol.style.Fill({
    color: &#x27;rgba(255, 255, 255, 0.6)&#x27;
  }),
  stroke: new ol.style.Stroke({
    color: &#x27;#319FD3&#x27;,
    width: 1
  })
});
var style &#x3D; [countryStyle, labelStyle];

var vectorLayer &#x3D; new ol.layer.Vector({
  source: new ol.source.Vector({
    url: &#x27;https://openlayers.org/en/v4.6.5/examples/data/geojson/countries.geojson&#x27;,
    format: new ol.format.GeoJSON()
  }),
  style: function(feature) {
    labelStyle.getText().setText(feature.get(&#x27;name&#x27;));
    return style;
  },
  declutter: true
});

map.addLayer(vectorLayer);
</textarea>
          <textarea class="hidden" name="css"></textarea>
          <textarea class="hidden" name="html">&lt;div id&#x3D;&quot;map&quot; class&#x3D;&quot;map&quot;&gt;&lt;/div&gt;
</textarea>
          <input type="hidden" name="resources" value="https://openlayers.org/en/v4.6.5/css/ol.css,https://openlayers.org/en/v4.6.5/build/ol.js,https://cdn.polyfill.io/v2/polyfill.min.js?features&#x3D;Set&quot;">
          <input type="hidden" name="data">
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        <pre><code id="example-source" class="language-markup">&lt;!DOCTYPE html&gt;
&lt;html&gt;
  &lt;head&gt;
    &lt;title&gt;Vector Label Decluttering&lt;/title&gt;
    &lt;link rel="stylesheet" href="https://openlayers.org/en/v4.6.5/css/ol.css" type="text/css"&gt;
    &lt;!-- The line below is only needed for old environments like Internet Explorer and Android 4.x --&gt;
    &lt;script src="https://cdn.polyfill.io/v2/polyfill.min.js?features=requestAnimationFrame,Element.prototype.classList,URL"&gt;&lt;/script&gt;
    &lt;script src="https://openlayers.org/en/v4.6.5/build/ol.js"&gt;&lt;/script&gt;
    &lt;script src&#x3D;&quot;https://cdn.polyfill.io/v2/polyfill.min.js?features&#x3D;Set&quot;&quot;&gt;&lt;/script&gt;
  &lt;/head&gt;
  &lt;body&gt;
    &lt;div id&#x3D;&quot;map&quot; class&#x3D;&quot;map&quot;&gt;&lt;/div&gt;
    &lt;script&gt;
      var map &#x3D; new ol.Map({
        target: &#x27;map&#x27;,
        view: new ol.View({
          center: [0, 0],
          zoom: 1
        })
      });

      var labelStyle &#x3D; new ol.style.Style({
        geometry: function(feature) {
          var geometry &#x3D; feature.getGeometry();
          if (geometry.getType() &#x3D;&#x3D; &#x27;MultiPolygon&#x27;) {
            // Only render label for the widest polygon of a multipolygon
            var polygons &#x3D; geometry.getPolygons();
            var widest &#x3D; 0;
            for (var i &#x3D; 0, ii &#x3D; polygons.length; i &lt; ii; ++i) {
              var polygon &#x3D; polygons[i];
              var width &#x3D; ol.extent.getWidth(polygon.getExtent());
              if (width &gt; widest) {
                widest &#x3D; width;
                geometry &#x3D; polygon;
              }
            }
          }
          return geometry;
        },
        text: new ol.style.Text({
          font: &#x27;12px Calibri,sans-serif&#x27;,
          overflow: true,
          fill: new ol.style.Fill({
            color: &#x27;#000&#x27;
          }),
          stroke: new ol.style.Stroke({
            color: &#x27;#fff&#x27;,
            width: 3
          })
        })
      });
      var countryStyle &#x3D; new ol.style.Style({
        fill: new ol.style.Fill({
          color: &#x27;rgba(255, 255, 255, 0.6)&#x27;
        }),
        stroke: new ol.style.Stroke({
          color: &#x27;#319FD3&#x27;,
          width: 1
        })
      });
      var style &#x3D; [countryStyle, labelStyle];

      var vectorLayer &#x3D; new ol.layer.Vector({
        source: new ol.source.Vector({
          url: &#x27;https://openlayers.org/en/v4.6.5/examples/data/geojson/countries.geojson&#x27;,
          format: new ol.format.GeoJSON()
        }),
        style: function(feature) {
          labelStyle.getText().setText(feature.get(&#x27;name&#x27;));
          return style;
        },
        declutter: true
      });

      map.addLayer(vectorLayer);
    &lt;/script&gt;
  &lt;/body&gt;
&lt;/html&gt;</code></pre>
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